1. Field of the Invention
The present invention relates to a method for manufacturing a microcrystalline semiconductor film, a method for manufacturing a semiconductor device which uses the microcrystalline semiconductor film, and a display device.
In this specification, a semiconductor device means all types of devices which can function by utilizing semiconductor characteristics, and a display device, an electro-optical device, a photoelectric conversion device, a semiconductor circuit, and an electronic appliance are all semiconductor devices.
2. Description of the Related Art
As one type of a field-effect transistor, a thin film transistor whose channel region is formed using a semiconductor film which is formed over a substrate having an insulating surface is known. Techniques in which amorphous silicon, microcrystalline silicon, or polycrystalline silicon is used for the semiconductor film which is used for the channel region of the thin film transistor have been disclosed (see Patent Documents 1 to 5). A typical application of the thin film transistors is a liquid crystal display television device, in which thin film transistors are practically used as a switching transistor for each pixel that constitutes a display screen.
A photoelectric conversion device is being developed in which microcrystalline silicon, which is crystalline silicon capable of being manufactured by a plasma CVD method, is used in a semiconductor film for photoelectric conversion (for example, see Patent Document 6).